The present invention broadly relates to a new and improved construction of an apparatus for electric pressure joining, especially pressure welding and pressure soldering.
In its more specific aspects the present invention relates to a new and improved construction of an apparatus for electric pressure joining, especially pressure welding and pressure soldering, and comprises a first electrode and a second electrode moveable towards and away from each other in acordance with working cycles. The first electrode possesses a first clamping surface and the second electrode possesses a second clamping surface. The first and second clamping surfaces face each other and are intended to securely clamp the workpiece to be welded or soldered therebetween and to feed the necessary electric current required for welding or soldering the workpiece.
In such apparatus the clamping surfaces of the electrodes are conventionally adapted to the size of the workpiece to be welded or soldered. In known machines of the above-mentioned type, heat is accumulated which cannot be sufficiently coped with even by forced or pressure cooling of the electrodes. This is particularly true during batch or series welding or soldering, for example, using hard solder, of relatively small workpieces such as, for example, welding or soldering contacts to the ends of terminal leads. As a result the electrodes or electrode inserts possessing clamping surfaces and inserted into the electrodes, have to be replaced in the known apparatus after a very short period of operation due to sparking and/or wear and/or deformation, all of which result in a corresponding stoppage or shutdown time.